I believe he means buying used games from Amazon, but I can't say for sure.

If that's what you mean, I'm pretty sure buying used games anywhere (Gamestop, eBay, etc.) isn't very good for the industry.
That said, I don't think you should stop buying used games, as I doubt used games are going to be main reason for the downfall of the game industry.

Well, if you drop your games in the amazon river they will probably be ruined.

lol

Anyways, no. It's simply another retailer. Are mobile games? Yes. Mobile games are high in quantity an low in quality. I only have 3 games on my Android, and those games are Zenonia 3-5. In other words, I've only found 1 good series so far.

It's just another retailer. It's also where I picked up a lot of my used games.

After E3 this year, I was totally disillusioned with the next generation of gaming. I was a Nintendo gamer all through the 90s and converted to Sony for the PS1, PS2, AND PS3. The PS4 isn't for me. Not at all. Gaming has been on a tend of lengthening development cycles, inflating budgets, and forgoing actual gameplay for a "cinematic experience." When I want a "cinematic experience," I just watch Game of Thrones. My console is for playing. I'm back to Nintendo now, and dropped probably around $1k~ on Amazon on a back-catalogue of Wii games over the last year or so.

So bad for the industry? I can't speak for anyone else, but for me personally, Amazon helped me reconnect to Nintendo. Many of my dollars will be going to them through Amazon over the next hundred or so years (unless I fancy some pre-order bonuses offered through other retailers).

So Anakin kneels before Monster Mash and pledges his loyalty to the graveyard smash.

...wut? You do realize you buy from sellers most of the time, not the site itself?

I'm well aware of that; it's just that the whole set-up on Amazon makes me uncomfortable. The good thing about eBay is that you can grill the seller and even get to know them. So you feel a lot happier buying from them.

I think these online retailers and used games in general help a lot of gamers of every generation to get games that would be tough to find new. I know that each generation of Nintendo consoles I get a massive amount of the previous systems games a year and a half into the lifespan of the current one. My Wii U has seen a large amount of play from Wii games, same case with the 3DS playing DS. Getting these games is best now rather than later when they become harder to find and/or afford.